Disclosure Has Spd Read 120, Locked 117km/h - Fine Is 120kmh

I recently received my disclosure documents (within hours of faxing) and the officer's notes were quite extensive.

My question is in the details the officer makes the following notes:

Direction: E/B Lane #:L1 Distance locked: 60 m Spd READ 120; locked: 117km/hr

My offence is HTA 128 - Speeding 120km/h in a 80 km/h zone.

Can someone explain what the difference of Speed Read of 120km/h versus locked 117km/hr? Is the official reading not 117km/hr rather than the amount charged of 120km/h? If so, was I over charged?

Do I have any arguments as a result of these two different numbers and the fact I was charged at the higher of the two versus the locked in reading? I have searched regarding this topic but cannot find anything directly related to the reading versus locked in measurements.

Thank-you in advance!

Radar or Lidar speeds do not have to be locked in at all. It is sufficient for the officer to simply state what the speeds were.

The highest speed the officer observed (and puts in his notes) is the speed he can write on the ticket and the speed that will stick in court. Locked or not is irrelevent.